Commit c0d6071a authored by Justin Tee's avatar Justin Tee Committed by Martin K. Petersen
Browse files

scsi: lpfc: Fix lockdep warning for rx_monitor lock when unloading driver 



Lockdep enabled kernels report a theoretical deadlock state where the
cmf_timer interrupt occurs while the rx_monitor ring is being destroyed.

During rmmod, the cmf_timer is cancelled prior to the
lpfc_rx_monitor_destroy_ring call.  This actually eliminates the need to
take the rx_monitor ring lock in lpfc_rx_monitor_destroy_ring.  Thus, just
remove lock/unlock of rx_monitor in lpfc_rx_monitor_destroy_ring.

Signed-off-by: default avatarJustin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20230301231626.9621-4-justintee8345@gmail.com


Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent bf21c9bb

drivers/scsi/lpfc/lpfc_sli.c

+2 −2
Original line number Diff line number Diff line
@@ -8080,16 +8080,16 @@ int lpfc_rx_monitor_create_ring(struct lpfc_rx_info_monitor *rx_monitor, 
/**

 * lpfc_rx_monitor_destroy_ring - Free ring buffer for rx_monitor

 * @rx_monitor: Pointer to lpfc_rx_info_monitor object

 *

 * Called after cancellation of cmf_timer.

 **/

void lpfc_rx_monitor_destroy_ring(struct lpfc_rx_info_monitor *rx_monitor)

{

	spin_lock(&rx_monitor->lock);

	kfree(rx_monitor->ring);

	rx_monitor->ring = NULL;

	rx_monitor->entries = 0;

	rx_monitor->head_idx = 0;

	rx_monitor->tail_idx = 0;

	spin_unlock(&rx_monitor->lock);

}









/**